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            <h2 class="title" style="clear: both"><a id="c2ctransfer"></a>Client to Client Transfer</h2>
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            <span class="sect2">
              <a href="c2ctransfer.html#fmwrkpeerserver">Identifying Peers</a>
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      <p>
                    It is possible to use a replica instead of a master to synchronize another
                    replica. This serves to take the request load off a master that might otherwise
                    occur if multiple replicas attempted to synchronize with the master at the same
                    time.
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                    For best results, use this feature combined with the delayed synchronization
                    feature (see <a class="xref" href="addfeatures.html#delayedsync" title="Delayed Synchronization">Delayed Synchronization</a>).
            </p>
      <p>
                    For example, suppose your replication group consists of four environments. Upon
                    application startup, all three replicas will immediately attempt to synchronize
                    with the master. But at the same time, the master itself might be busy with a heavy
                    database write load.
            </p>
      <p>
                    To solve this problem, delay synchronization for two of the three replicas. Allow
                    the third replica to synchronize as normal with the master. Then, start
                    synchronization for each of the delayed replicas (since this is a manual process,
                    you can do them one at a time if that best suits your application).
                    Assuming you have configured replica to replica synchronization correctly, the
                    delayed replicas will synchronize using the up-to-date replica, rather than using
                    the master.
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      <p>
                     When you are using the Replication Manager, you configure replica to replica synchronization by
                     declaring an environment to be a peer of another environment. If an
                     environment is a peer, then it can be used for synchronization purposes.
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              <h3 class="title"><a id="fmwrkpeerserver"></a>Identifying Peers</h3>
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        <p>
                            You can designate one replica to be a peer of
                            another for replica to replica synchronization.
                            You might want to do this if you have
                            machines that you know are on fast, reliable
                            network connections and so you are willing to
                            accept the overhead of waiting for
                            acknowledgments from those specific machines.
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        <p>
                        Note that peers are not required to be a
                        bi-directional. That is, just because machine A
                        declares machine B to be a peer, that does not mean
                        machine B must also declare machine A to be a peer.
                    </p>
        <p>
                            You declare a peer for the current environment
                            when you add that environment to the list of known
                            sites. You do this by
                            <span>specifying the
                                <code class="literal">DB_REPMGR_PEER</code> flag to
                                    
                                    <span><code class="methodname">DbEnv::repmgr_add_remote_site()</code>.</span>
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